By: Heather Rhoades
Bone meal fertilizer is often used by organic gardeners to add phosphorus to garden soil, but many people who are unfamiliar with this organic soil amendment may wonder, “What is bone meal?” and “How to use bone meal on flowers?” Keep reading below to learn about using bone meal for plants.
What is Bone Meal?
Bone meal fertilizer is essentially what it says it is. It is a meal or powder made from ground up animal bones, normally beef bones, but they can be the bones of any animal commonly slaughtered. The bone meal is steamed to increase its availability for plants.
Because bone meal is made from mostly beef bones, some people wonder if it is possible to get Bovine spongiform encephalopathy, or BSE (also known as Mad Cow Disease), from handling bone meal. This is not possible.
First, the animals that are used for making bone meal for plants are tested for the disease and cannot be used for any purpose if the animal is found to be infected. Second, the plants can’t absorb the molecules that cause BSE and, if a person is truly worried, then he or she need only to wear a mask when using the product in the garden, or purchase non-bovine bone meal products.
At any rate, the chances of getting mad cow disease from this garden fertilizer are slim to none.
How to Use Bone Meal on Plants
Bone meal fertilizer is used to increase phosphorus in the garden. Most bone meal has a NPK of 3-15-0. Phosphorus is essential for plants in order for them to flower. Bone meal phosphorus is easy for plants to take up. Using bone meal will help your flowering plants, like roses or bulbs, grow bigger and more plentiful flowers.
Before adding bone meal for plants to your garden, have your soil tested. The effectiveness of bone meal phosphorus drops significantly if the pH of the soil is above 7. If you find that your soil has a pH higher than 7, correct your soil’s pH first before adding bone meal, otherwise the bone meal will not work.
Once the soil has been tested, add bone meal fertilizer at the rate of 10 pounds (4.5 kg.) for every 100 square feet (9 sq. m.) of garden that you are amending. The bone meal will release phosphorus into the soil for up to four months.
Bone meal is also useful for balancing out other high nitrogen, organic soil amendments. For example, rotted manure is an excellent source of nitrogen but it tends to lack significant amounts of phosphorus. By mixing bone meal fertilizer in with rotted manure, you have a well balanced organic fertilizer.
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Step 1. Clean the Bones
Your first step is to remove any remnants of fat and meat from the bones. Consider scraping the surface thoroughly till they are spanking clean if that isn’t effective, pressure cook the bones for 5 minutes.
Step 2. Bake
After cleaning the bones, bake them at 400-450°F or until they get all dry and fragile. Ideally, small and medium bones will take an hour to reach that stage. Keep them aside and let them cool down.
Step 3. Fragment
Transfer the bones to a tough bag or sack and use a bat or a rolling pin to smash them into tiny fragments about an inch long.
Step 4. Grind
Toss the bone pieces in a blender and grind them thoroughly till they form a fine mixture. Mix the bone dust with wood ash or sprinkle it solo on your garden bed.
Still confused? Learn how to make a dry bone meal in this video here.
When to Use Bone Meal
Numerous studies have demonstrated that roses, like most terrestrial plants, maintain symbiotic relationships with beneficial fungi. Adding a phosphate like bone meal will decrease the ability of the fungi to colonize the rose roots. Without these fungal partners, rose roots must work harder to extract water and nutrients from the soil. This means that the roses must put additional resources into root growth at the expense of other tissues and functions.
Phosphorus helps a plant convert other nutrients into usable building blocks with which to grow. This aids in the process of photosynthesis. This is because bone meal is a meal or powder made from ground-up animal bones, normally beef bones. The bone meal is steamed to increase its availability for nutrients in plants, according to Epic Gardening.
Many types of natural fertilizers can have a low phosphate count, and bone meal is a valuable source of slow-acting and long-lasting phosphorus. University of Missouri Extension says it should be mixed into the soil because it does not move down readily with watering. Only use about 1 heaping tablespoon per plant. This contributes to stronger, more established roses, and there are some 100 species of roses, with the most common ones being the pink, yellow or dark-crimson species.
What Can Bone Meal be Used for in Gardening?
Bone meal is used as an organic soil amendment. It is commonly used to boost the level of phosphorus in soil. However, it can also be used to add other essential nutrients, including calcium and nitrogen.
Bone Meal for Phosphorus
Bone meal is mainly used as a source of phosphorus. Plants need phosphorus during nearly every stage of their development. Because of its density, it takes a long time for bone meal to release all of its phosphorus stores. As such, a single application of bone meal can last as long as four months.
Bone Meal for Calcium
Bone meal is also high in calcium. Calcium is considered a secondary plant nutrient.
It is required during the development of a plant’s cell walls. Calcium is also responsible for maintaining the salinity of the soil. Without an adequate amount of calcium, soils may be thrown off balance. Signs of calcium deficiency include stunted growth, shallow roots, growth abnormalities, and more.
With that said, a soil with a pH rating that is higher than seven may have an overabundance of calcium. Excess calcium can block plants from absorbing sufficient amounts of fundamental nutrients. This is yet another reason why soil testing is so important.
Bone Meal for Nitrogen
Some bone meal also contains small amounts of nitrogen. However, bone meal alone is not usually enough to amend nitrogen-deficient soil.
Instead, we recommend adding a nitrogen-rich composted manure. Bone meal and manure can be combined to create a highly beneficial organic fertilizer.
Bone Meal For The Spring Flower Garden
Get the ground ready for planting by adding bone meal to the soil.
It sounds a bit gross to use crushed bones when fertilizing, but the fine, powdery substance works wonders for your plants. Bone meal is a great source of phosphorus which helps establish good roots, and without good roots, plants don’t grow as well.
Bulbs, like the ones in my photo here, will appreciate some bone meal mixed into the planting soil. Your tulips and daffodils will produce more blooms, as will any flowers planted in spring.
Organic Bone Meal is the perfect addition to an organic garden. I add it to the bare garden soil in spring before it’s time to plant. It helps make the soil better for everything you plan to grow, as long as you don’t overdo it.
Use it as a soil amendment around perennials too. I sprinkle it around the hydrangea shrub and other perennials in the yard once the snow is gone. Rake it into the soil and be careful around the shallow roots. Bone meal replaces depleted phosphorus and will get the plants off to a good start for summer growth.
I buy mine in 4.5 lb. bags and directions say to use 1 teaspoon mixed into the dirt for bulbs. For shrubs, such as the hydrangea, apply 1 to 2 pounds (2.25 cups of bone meal equals 1 pound). Directions are on the bag, or box and it can even be used in pots.
Blood meal is a different product and can be used to supply the nitrogen your garden needs. Nitrogen keeps plants looking green. Use it if the leaves on your plants begin to turn yellow.
Be careful when using fertilizer, even organic fertilizer (and make sure it is truly organic!) like bone meal and blood meal, because it is still possible to use too much and damage the plants.
Annuals and Perennials will grow better with bone meal.
Above you can see the lush growth of my nasturtiums (annuals), and hydrangea (leaves) and coneflower (echinacea) which are perennials.
(All photos in this post are my own, and are not free to use.)
What Might You Use Instead?
There are 3 products I generally use when planting in my organic garden.
I talk about them in my next article: Bone Meal Alternatives
Update: Some people say I’m scare-mongering with this post. Look, I don’t know much about the research going on now – it’s just that when I was studying organic gardening, I was taught to avoid using it because my national organic standard didn’t allow it, and still doesn’t allow it. You’re certainly welcome to use it. I’m not trying to offend or scare anyone. Have a nice day!
Fertilizing Peonies in the Perennial Flower Garden
Many perennials, including peonies, benefit from a start-of-season mulch application of homemade compost. While many of these perennials are also fed fertilizer products early in spring, wait a few weeks more before feeding peony plants.
Watch for the peony stems to appear, grow to about one foot, and start to put up tiny flower buds. Apply slow-release organic fertilizer when the first tiny flower buds appear. Water deeply following peony fertilizer application.
I hope you’ve learned something about peony fertilizer and when to feed these lovely flowering perennials! What kinds are you growing this year?
“Few flowers can contend with the ultimate queen of spring, the peony. Their large flower heads and billowy, ruffled blooms come in a dizzying array of pinks, corals, cranberries, whites, yellows, and reds. Many carry a sweet fragrance, and most are long lasting in the vase.”Floret Farm’s Cut Flower Garden: Grow, Harvest, and Arrange Stunning Seasonal Blooms, by Erin Benzakein and Julie Chai
Flower buds on ‘Festiva Maxima’ peony plants in early June just before blossoming ‘Bowl of Beauty’ pink peony flower blooming in mid-June
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